The present invention relates to jigs for aligning a workpiece with respect to a handsaw, and relates more particularly to a modelmaker's jig for performing miter cuts.
A conventional miter box consists of an open channel-like structure. A workpiece rests on the floor of the channel, and a plurality of slots in opposing channel walls guide a saw at a fixed angle across the workpiece. Conventionally, the slots define cuts of 45, 90 and 135 degrees across the channel.
In lieu of opposing slotted walls for guiding the saw, it is possible to have a saw-guiding frame pivotally mounted on a vertical shaft. The frame may be locked at any position, so as to permit the alignment of the saw at any selected angle. Miter boxes with such a pivoting saw frame construction generally include one vertical side wall, against which an edge of the workpiece is pressed to align it.
FIGS. 1A, 1B and 1C show, respectively a top, side and cross-sectional view of a prior art modelmaker's jig for performing miter cuts. One such jig 1 is sold in the United States by X-ACTO as their model No. 7533 miter box, and has overall dimensions of approximately 5 cm. width.times.5 cm. height.times.15 cm. length. This jig 1 has front and back walls 2,3 on opposing sides of floor 4, defining a channel for aligning a workpiece. Slots 5 in walls 2,3 guide a saw across the floor 4 for making miter cuts in a workpiece (not shown) supported on the floor. This jig is widely accepted by modelmakers for performing miter cuts.
Nonetheless it has drawbacks. The workpiece, which is generally a small, e.g., 0.5-1.0 cm. round or rectangular rod stock, or narrow sheet strip, must be manually aligned against the wall 2 or 3 with one hand, in registry with a cut, while the other hand moves the saw. During this operation pressure must be exerted against the miter box to prevent its sliding about on the tabletop. These constraints are partially addressed in the device of FIGS. 1A-1C. First, a plurality of graduated grooves 6 in the floor 4 hold workpieces of different widths in a proper orientation. Second, a flange 7 extending below the floor 4, may be butted up against the edge of a tabletop, thus permitting the box to be maintained in reasonably fixed alignment by the pressures exerted by the saw and by the hand holding the workpiece. Each of these improvements to the classical miter box design makes its use easier. However, because the box must be held down, and the workpiece first marked, then aligned, then held in position before commencing the saw cut, working with the prior art box requires care.